Descriptive Text : Fauna

Bottlenose Dolphins 

Bottlenose dolphin with young.JPG

Bottlenose dolphins Tursiops truncatus ) are the most common and well known species of dolphins . Habitat is located in warm waters around the world and can be found in almost all waters except the Arctic Ocean and the Southern Ocean.
Bottlenose gray nose dolphins that vary from dark gray at the top near the dorsal fin to a light grayish gray at the bottom. This color pattern makes them hard to see from the top and bottom. Adult nose dolphins have a length of between 2 to 4 meters and weights from 150 to 650 kilograms.

KINGDOM: ANIMALIA
Filum: Chordata
Class: Mamalia
Ordo: Cetacea
Famili: Delphinidae
Genus: Tursiops
Spesies: T. truncatus


Life cycle

Baby
Baby dolphins (also called calf) are born after the 11-12 months pregnant period.

Teenagers
After the age of 3-6 years, teenage dolphins will decide their own way of life to remain in the herd of the mother or leave the mother and herd.

Adult
At the age of 5-13 years, adult female dolphins will return to the group in which they were born. Dolphins are also known as pods, for flocks with hundreds of dolphins in them often called superpods. Dolphins achieve sexual maturity at around 7-12 years for females and 10-15 years for 
males.

The Marriage Period
Around the age of 12 years, male dolphins will look for a partner to breed. They are sometimes involved in acts of aggression as a form of competition for females.Mating season usually occurs during spring. Dolphins will explore the introductory period with a partner for days. At this time, the couple will be seen always swimming together and caressing each other with their fins. The process of mating takes place very quickly, usually in seconds.
Birth Process
Unlike land mammals, the dolphin's birth begins with the tail coming out first.This is because if the head comes out first, there will not be enough time for the baby to reach the surface to breathe. The process of dolphin birth takes about 3 hours, and during this process there will be blood, which will provoke a predator like a shark to approach. To protect the mother dolphins during delivery, other dolphins in the group will form a circle around them. Newborn dolphins will be assisted by the mother brought to the surface in order to breathe the air. Female dolphins will usually give birth about every 4 or 5 years. They choose to care for their children first enough to be self-sufficient, before containing the next child. A dolphin can have up to 11 children in their lifetime, and can still mate until age over 40 years. The life expectancy of a male dolphin is 40 years, and 50 years for a female.

Food
Fish and squid are the main food of dolphins. The famous dolphins love hunting in groups by feeding their food (fish) into bait balls before they are executed. 
Predators
The main predator of a dolphin is a shark. But humans also play a major role in the reduced population of dolphins. Meat of dolphins is consumed in a small number of countries around the world, including Japan and Peru.

Fun Fact

Bottlenose dolphins live in groups. Adults and adult dolphins are always strongly associated in a group, but there are often many adult dolphins in association with other groups. This is what proves that they have a high adaptability, so many are kept freely and easily trained because of their high intelligence, even among marine mammals, bottlenose dolphins are the most intelligent.

This type of dolphin brain is bigger than any other dolphin brain. In addition they have a cerebral cortex 40% larger than humans. Cerebral cortex is a brain region that functions for social communication, abstract processing information, problem solving, and intelligence in accepting new things.

These marine mammals have poor eyesight and olfactory. Instead, the bottlenose dolphins have a sonar system that serves to help identify prey and location in the water using sound frequency emissions. The prey will be detected based on the reflection of the received frequency at the lower part of the jaw and transmitted to the brain with the aid of an organ called a round melon made of oil and serves to exert a very high frequency towards the prey.

The bottlenose dolphins developed various methods to capture their prey, in addition to the use of high-frequency sound, one of which is by using sponges that were thought to flourish in the 19th century. This sponge is placed on the rostrum (muzzle) to protect it from rocks, shells, or other objects that can injure the muzzle. Once the prey is seen, then the sponge will be released in order to catch the prey. But not all individuals apply this technique.

Dolphins communicate with "whistles" and use "names" to identify each other. Some scientists suspect that dolphins have a special calling sign and use a special greeting when parted with his friend.



Question
1. What is Family of Bottlenose of Dolphins? 
A. Animalia
B. Chordata
C. Mammals
D. Cetacea
E. Delphinidae

2.In the following habitat of Bottlenos of Dolphins, except... 
A. Warm water
B.Artic ocean
C. Pacific ocean
D. Atlantic ocean
E. South china sea

3. What is diet of Bottlenose of Dolphins? 
A. Fish and Squid
B. Other dolphins
C. Shark
D. Humant
E. Fitoplankton

4.Dolphins achieve sexual maturity at around ... years for females an ... years for 
males.
A. 10 - 15, 7-12
B. 3-6, 6-3
C. 7-12,  10 - 15
D. 7-12, 5 -13
E. 10 - 15, 5-13

5. The life expectancy of a male dolphin is .... years. 
A. 50
B.30
C.35
D.40
E 45

Answer
1.E, 2.B, 3.A, 4.C, 5.D

References

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